The 6C2 monoclonal antibody reacts with mouse Toll-like receptor 2 (TLR2). Mouse TLR2 is expressed by the myeloid lineage, including macrophage and dendritic cells in splenocytes and the RAW264.7 cell line. To date, at least twelve members of the Toll family have been identified in human and mouse. This family of type I transmembrane proteins is characterized by an extracellular domain with leucine-rich repeats and a cytoplasmic domain with homology to the type I IL-1 receptor. Two of these receptors, TLR2 and TLR4, are pattern recognition receptors and signaling molecules in response to bacterial lipoproteins and have been implicated in innate immunity and inflammation. TLR2 is expressed on the surface of cells and is responsible for distinguishing different pathogens.